An OTFT‐driven rollable OLED display

Abstract— An 80‐μm‐thick rollable AMOLED display driven by an OTFT is reported. The display was developed so as to be rollable in one direction with an integrated OTFT gate driver circuit. It was successfully operated by an originally developed organic semiconductor, a peri‐xanthenoxanthene derivative. The display retained its initial electrical properties and picture quality even after being subjected to 1000 cycles of a roll‐up‐and‐release test with a radius of 4 mm.     

Development of soft x-ray time-resolved photoemission spectroscopy system with a two-dimensional angle-resolved time-of-flight analyzer at SPring-8 BL07LSU

We have developed a soft x-ray time-resolved photoemission spectroscopy system using synchrotron radiation (SR) at SPring-8 BL07LSU and an ultrashort pulse laser system. Two-dimensional angle-resolved measurements were performed with a time-of-flight-type analyzer. The photoemission spectroscopy system is synchronized to light pulses of SR and laser using a time control unit. The performance of the instrument is demonstrated by mapping the band structure of a Si(111) crystal over the surface Brillouin zones and observing relaxation of the surface photo-voltage effect using the pump (laser) and probe (SR) method.     

Characteristics of lightning surges observed at 77 kV substations

In order to improve power supply reliability, it is necessary to prevent lightning faults in transmission lines and substation apparatus. However, faults are caused occasionally in lower-voltage power systems, particularly at the 77 kV level. The governing factor for insulation strength of substation apparatus is the lightning impulse voltage, and it is necessary to know the voltage level and distribution in a substation caused by lightning surges in order to investigate rational insulation coordination. For this purpose, the authors measured lightning surges at two 77 kV conventional substations from 1990 to 1993. In this paper, the characteristics of induced lightning surges and back flashover lightning surges are described. Comparisons of related surge voltages at two substations, the power line phases in grounding faults, and the equivalent capacitance of the substations are also discussed.